Earth moving device



Feb. 23, 1932.

R. L. ,HARRISON EARTH MOVING DEVICE Filed March- 20, 1929 2 Sheets-Sheet l Y J 7Z@67ZZO7" 2770/20 [Wm 7215022 Feb. 23, 1932. HARRISON. 1,846,592

EARTH MOVING DEVICE Filed March 20, 1929 2 Sheets-Sheet 2 Patented Pea-23, 1932 PATENT- OFFICE UNITED STATES- RAYMOND LI HARRISON, 0F ALBUQUERQUE, NEW MEXICO EARTH MOVING DEVICE Application filed March 20, 1929. Serial No. 348,416.

My invention relates to earth moving devices and particularly to devices which are connection with the manipulation of tiltable earth moving or excavating devices is that of controlling the position of the cutting edge with respect to the surface of the ground. To

my knowledge, vehicle drawn excavating or earth removing devices which have heretofore been employed have not been provided with means for positively controlling the position of the above mentioned cutting edge. The need for such a controlling means is evidenced particularly in connection with the moving or excavating of soil which varies in surface contour, hardness, constituency and the like. In other words, in order to adapt a vehicle drawn shovel or earth removing means for eificient performance under the varied operating conditions presented by soil characteristics and the like, the positive control of the position of the soil en aging or cutting edge of the device is, ecidedly important.

It is one of the primary objects of my pres- 1 ent invention to provide an earth moving device of improved practical construction having an earth carrier which may. be readily drawn across the surface of the ground and conveniently tilted so as to positively control the position of the cutting edge thereof.

Another object of my invention is to provide an improved earth moving device of the above mentioned nature which is adapted to be drawn across the surface of thesoil by any suitable vehicle, the position of the cutting edge of the earth carrier being controlled from a remote point as for example from the position occupied by the driver of the vehicle, with a minimum amount of skill and effort on the part of the operator.

Still another and more specific object of my invention is to provide a device as above set forth having a pivotally mounted scoop or shovel which is adapted to be secured in various angular positions by means of a suitable latching device and my invention contemplates the further provision of conveniently operable means for positively moving said latching device to vary the angular position of the scoop, whereby the position of the cutting edge thereof with respect to the surface of the soil may be effectively governed.

Still another object of my present invention is to provide not only a positive means for varying the angular position of the pivoted scoop or earth carried but also to provide a means which will serve to instantly varythe position of the carrier with little effort on the part of the attendant and to this end I propose to provide an actuating device which is instantly responsive to control means conveniently positioned with respect to the operator.

These and other objects will be more apparent from the following detailed description when considered in connection with the accompanying drawings, wherein Figure 1 is a side elevational View of an earth removing device which is representative of one embodiment of my present invention, the same being shown in association with a tractor of conventional design;

Figure 2 is a reduced side elevational view of the device shown in Figure 1, disclosing the earth carrying means or scoop with the cutting edge thereof in cutting position;

Figure 3 is an enlarged detailed sectional View of the mounting for the actuating lever taken substantially on the line 33 of Figure 1;

Figure 4 is a plan view of the device shown in Figure 1 with the portion of the earth carrying scoop broken away to more clearly disclose the structural characteristics there- 0 Figure 5 is a fragmentary elevational view of the earth carrying device with the cutting edge thereof shown n earth carrying position; and I Figure 6 is a similar-side elevational view disclosing the cutting edge of the earth carrying device or scoop in an extreme spreading position.

Referring now to the drawings more in detail wherein like numerals have been employed to designate similar parts throughout the various figures, it will be observed that my invention contemplates the provision of a suitable earth carrying means or scoop 10 which comprises a substantially semi-cylindrical shell 12 and end plates 14 positioned at each extremity of said shell. Suitably secured along one of the longitudinal margins of the shell 12 and along one of the margins of each of the end plates 14, as by means of bolts 16, is a blade 18 which is provided with a cutting edge 20. This earth carrying means or scoop 10 is rotatably supported by a shaft 22 which extends between bearings 24 secured to the outer surfaces of the end plates 14. Abifurcated drawbar or yoke 26 is coupled with the bearings 24 and the shaft 22 so as to enable the scoop 10 to be freely rotated about its axis. Thus if the yoke 26 is moved to the right, as viewed in the various figures, and no means is provided for securing the scoop 10 against rotation, said scoop will be rolled across the surface of the soil, which surface is indicated by the line 28. It is to be understood that if the cutting edge 20 of the scoop occupies the position shown by the dot and dash lines in Figure 1 and the same is drawn across the surface 28, earth will be gathered by the scoop, providing that said scoop is secured against rotation.

To secure said scoop against rotation in various positions, I provide a plurality of' lugs or stop members 30,32 and 34 along the medial portion of the peripheral surface of the shell or casing 12. 'These lugs are adapted to be received between a pair of co-operating latch members 36 and 38 carried at the rear extremity of a horizontal link member 40. The latch member 36 is secured in a fixed position upon the link 40 while the latch member 38 is-pivoted at 42. By this construction the latch 38is free to swing upwardly in response to the engagement therewith by one of the lugs 30, 32 or 34 when said lugs are moved toward the latching members in a clockwise direction as viewed in the drawings. In Figure 1 the lug is shown in locked position between the latch members 36 and 38 and when secured in such position the blade 18 occupies a substantial- 1y horizontal position. If a movement to the .right is imparted to thelink 40, the lug 30 together with the blade 18 will be moved to the dot and dash position as shown. The forward extremity of the link is pivoted to the upper end of an actuating lever 44 and the lower end of this actuating lever 44 is pivotally secured to :1 depending frame 46 as by means of a bolt 48. This depending frame 46 is secured in any suitable manner at its upper end to the drawbar or yoke 26 and is provided with a plurality of apertures 50 which register with companion apertures 52 provided in the lower end of the lever 44. Thus, in order to vary the amount of power transmitted by the lever 44 in response to the actuation of a pressure mechanism 54, about 8 to be described, it is only necessary to change the position of the bolt 48 with respect to the registering openings 50 and 52.

This pressure mechanism 54 comprises a suitable cylinder 56 and a piston rod 58 which is adapted to be moved in response to oil or other suitable medium introduced within the cylinder 56 through a flexible conduit 60. Pivotally connected to and interposed between the outer extremity of the pis ton rod 58 and an intermediate portion of the actuating lever 44, is a link 62, and it will thus be apparent that reciprocation imparted to the piston rod 58 will effect the movement of the actuating lever 44. In the particular type of pressure mechanism disclosed, the piston is adapted to be urged to the left, Figure 1, in response to the introduction of oil into the cylinder 56 and a suitable coiled spring 64 serves continuously to urge the lever 44 to the right, this coiled spring being interposed between the cylinder and the lever.

The upper extremity of the conduit is connected with a valve such as the disclosed three-way valve 66 carried by any suitable drawing means or vehicle which inthe present instance I have shown as being a conventional tractor 68. This valve 66 may be actuated by moving a lever 70 which may be conveniently operated by an attendant occupying aseat 72. One side of the valve 66 is connected, through the agency of a suitable pipe 74, to the egress side of a suitable pump mechanism 76. The other side of the valve 66 is connected by means of a pipe 78 and a pipe 80 to the ingress side of the pump mechanism 76. This pipe 80 connects with the usual reservoir 82. Thus, when the valve handle 70 occupies the position shown in Figure 1, the oil is locked within the cylinder 56 and the conduit 60, thereby securing the actuating lever 44 in a fixed position. By moving the lever in a clockwise direction from the position shown in Figure 1, until it assumes a horizontal position, oil will enter the conduit 60, thereby applying pressure to the piston within the cylinder 56 so as to cause the actuating lever to be moved to the left. If the handle 70 is moved to a vertical position in a counter-clockwise direction from the position shown in Figure 1, the pressure within the cylinder will be relieved and the actuating lever 44 will move to the right under the in fluence of the spring 64. Obviously, various forms of pressure control devices may be employed to positively and instantaneously effect the movement of the actuating lever 44 without departing from the spirit and scope of this invention. My invention contemplates the use of various forms of mechanisms which may be conveniently operated by an attendant for moving the actuating lever. It will be apparent from the device illustrated that the operator occupying the seat 72 may tion by mere manipulation of the handle 70.

The positive control of the scoop 10 enables the cutting edge 20 to be positioned in accordance with the operating conditions to which the device is being subjected. Suppose 'for example that'a light out is desired to be made into the soil. In such an instance the oper-' ator can accurately and positively govern the angular position of the blade 18 in accordance with the depth of out which is to be taken. Also in instances where the soil is hard in some spots and soft in others it is desirable to vary the angularity of the blade and my improved device enables the positioning of the blade with a' minimum amount of efl'ort and skill. It will be noted that the drawbar or yoke 26 is connected with the tractor 68 by a pivotal or universal coupling 84, Figures 1 and 2. In Figure 2 the tractor is shown as traveling over an elevation 86 which causes the coupling 84 to be lowered and hence changes the angular relation between the cutting blade 18 and the-surface of the soil. Such a variation might cause too great a cut to be taken were it not for the fact that my improved controlling mechanism enables the instantaneous adjustment of the angularity of the blade to meet the particular needs incident to its use. drawn into the scoop 10, the valve lever may be operated so as to cause the tilting of the scoop to the position shown in Figure 5 which is the position occupied by the scoop when the material gathered thereby is being moved from one position to another. In other words, this is the carrying position as distinguished from the cutting position shown in Figure 2. In Figure 6 the latch members 36 and 38 are shown in association with the lug 32. In such a position the scoop occupies a spreading position. If it is desired to position the scoop so that the blade 18 will not engage the soil, the lug 34 can be carried into association with and locked in position by the latch members 36 and 38 and this position might be called the trailing position.

In the specification and claims I have employed the terms bowl, earth carrying means, scoop, and shovel in describing the device 10 which is pivotally mounted upon the frame or yoke 26. All of these terms are correctly descriptive of the device 10. In the trade, the term tbowl is commonly employed to designate an earth carrying means f the pivotally supported type and hence in some of the claims this term bowl has been employed. It should be understood, however, that by using the word bowl? in the specification and claims I do not in any sense limit myself to the use of any particular shape of earth carrying device but contemplate any After a load of soil has been suitable receptaclewhich is adapted to receive soil, move the said soil from one position to another and to discharge the soil when desired. In other words, my invention contemplatesthe use of any earth carrying device of the type set forth above whether it be referred to as a scraper bucket, scoop, shovel, bowl or the like. 7 V

In order to eflect the discharge or dumping of a load of soil carried by the scoop, it is only necessary for the attendant to exert a pull on aflexible connector'or cord 88, Figures l and 2. This cord is secured to the upper extremity of an L shaped trip arm 90 which is pivoted to an uprlght frame member 92 carried by the drawbar 0r yoke 26. This trip arm passes between the members which'form the link .40, and rollers 94, carried by said arm when moved upwardly in response to the pull on the cord 88, cause the link to be swung upwardly so as to disengage the latch members 36 and38 from the peripheral lug with which'they may be associated. The frictional en'ga ement 'of the scoop with the ground is su cient to cause the same to be rotated as the tractor 68 continues to move forwardly, thereby causing the soil to be discharged in the proper place. By releasing the cord 88 at the proper interval, the desired lug may be locked in osition between the lugs 36' and 38. To acilitate the movement of the scoop along the surface of the soil I provide a pair of oppositelydisposed shoes 96.

From the foregoing it will be apparent that my invention contemplates the provision of a new improved earth moving de- V166. of simple and practical construction which maybe conveniently operated and accurately adjusted. The controllingv means located in a convenient position for the operator provides a means whereby instantaneous and accurate positioning of the cutting edge of the earth carrying device or scoop may be effected. As already pointed out, the provision of such a controlling means is very' desirable in instances where soil character istics require that the angularity of the cutting blade be varied in accordance with such characteristics. Obviously the mechanism for controlling the reciprocation of the link 40 and consequently the angular positioning of the scoop 10 is not limited to the specific mechanism disclosed. In addition to the controlling feature presented by the fluid pressure device, the disposition of the bolt receiving openings provided at the lower extremity. of the actuating lever serve to enable a variation in the control of the angular displacement-of the scoop 10. This pivotal mounting for the actuating lever also enables more or less power to be transmitted to the link 40 as the conditions may demand. In other words, under certain conditions, suflicient power is transmitted for.

operating purposes when the bolt 48 of the lever is positioned within the uppermost registering apertures. However, when it is desired to transmit increased power, said bolt may be positioned in another of said registering openings. By means of my improved cutting edge controlling device, the scoop or what has been commonly termed the fresno, may be moved to the spreading position shown in Figure 6. By actuating the valve handle 70, the cutting edge may be positioned for light or heavy spreading as the case may demand. Similarly, the device may be adjusted for heavy and light cutting operations. By positioning the scoop with the lug 34 locked in position between the latch members 36 and 38, said scoop will occupy a convenient trailing position. It will thus be apparent that my improved controlling mechanism serves to positively, instantly and accurately position the cutting edge of the earth carrying device from a remote position with a minimum amount of effort and skill.

From the foregoing it will also be apparent that my improved earth moving device is of such a construction as to enable the carrier or fresno to be revolved about its axis independently of themovement of the drawbar or yoke 26. If the carrier or fresno were secured in a fixed position to and movable with the drawbar, the position of the cutting edge 20 with respect to the soil would be varied each time the drawbar coupling 84 was raised or lowered. Thus, as shown in Figure 2, when the tractor 68 moves over the elevation 86, the coupling 84 is lowered. Under such conditions the operator can move the fresno so as to maintain a constant relation between the cutting edge thereof and the surface of the earth regardless of the movement which is imparted to the drawbar. The position of the blade 18 and its cutting edge 20 shown by the solid lines in Figure 2 discloses the fresno as taking a like cut across the surface of the soil. Were it not for the fact that the operator can raise the cutting edge when the coupling 84 is lowered to the position shown in Figure 2, the fresno would take a out which might be too deep. In some instances the blade of the fresno might be moved to the dot and dash position shown in Figure 2 which represents the carrying position of the fresno. Thus it will be apparent that the fresno, in riding over obstructions, can be controlled so as to prevent said obstructions from being torn down or in other words the bowl can be controlled independently of the position of the drawbar. In riding over an obstruction it would, of course, be desirable to tilt the carrier blade 18 upwardly to the osition shown by the dot and dash lines of igure 2 and in some instances it may be desirable to maintain the carrier blade 18 in a horizontal position when the tractor is passing over an obstruction. All of these various positionsof the carrier or fresno may be accomplished by the simple and convenient adjustment of the lever 70.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:

1. In an earth moving device adapted to be moved across the surface of the ground, the combination with a rotary earth carr ing bowl having a material receiving edge, 0 hydraulically operable means for adjustably controlling the position of said material receiving edge with respect to the surface of the material with which the bowlis associated,

and means for pivotally supporting said bowl at opposite sides thereof.

2. In an earth moving device adapted to be moved across the surface of the ground, the combination with a rotary earth carrying bowl having a material receiving blade, hydraulically operable means for adjustably controlling the angular relation of said blade with respect to the surface of the material with which the carrieris associated, and a frame on opposite sides of said bowl for pivotally supporting same.

' 3. In an earth moving device of the class described which is adapted to be moved across the surface of the ground, the combination of an earth carrying bowl having a material receiving edge, latch means for securing said edge in various positions with respect to the surface of the material with which the bowl is associated, and hydraulically operable means for controlling the position of said latch means.

4. In an earth moving device of the class described adapted to be drawn across the surface of the ground, the combination with an earth carrying bowl having an earth receiving edge, means for adjustably controlling the position of said edge with respect to the surface of the material with which the bowl is associated, said means including a latching mechanism, and hydraulically operable means for shifting said latching mechanism to variously position the receiving edge of the bowl.

5. In an earth moving device of the class described, which is adapted to be drawn across the surface of the ground, the combination with a rotary earth carrying bowl having its axis of rotation extending therethrough, of hydraulically operable means for adjustably controlling the rotary displacement of the bowl about its axis.

6. In an earth moving device of the class described, a shiftable earth carrying bowl having an earth receiving edge, means for connecting said bowl with a tractive mechanism, latch means for securing said shiftable bowl in a fixed position, and hydraulically operable means for shifting said latch means so as to vary the position of the earth receiving edge of the bowl.

7 In an earth moving device of the class described, the combination with a rotary earth carryin bowl having a material receiving edge an a mechanism for urging said carrying bowl across the surface of the ground, of hydraulically operable means directly 'connectible with the bowl for adjustably positioning the material receiving edge thereof with repect to the surface of the material with which the device is associated, and manually shiftable means operable from a position adjacent the urging mechanism for controlling the actuation of said hydraulical 1y operable positioning means.

8. In an earth moving device adapted to be moved across the surface of-the ground. the combination with an earth carrying means having a material receiving edge and a mechanism for moving said carrying means,

of a latching mechanism for operatively engaging said carrying means, and hydraulic actuating means operable from a point adjacent the moving mechanism for shifting said latching mechanism to vary the position of the material receiving edge of the carrying means with respect to the surface of the material with which the same is associated.

9. In an earth moving device adapted to be moved across the surface of the ground, the combination with an earth carrying means having a material receiving edge and a mechanism for moving saidcarrying means across the surface of the ground, of a latching mechanism for operative engagement with said carrying means, hydraullc actuating means for shifting said latching mechanism to variously position the material receiving edge of the carrying means, and means for disengaging the latching mechanism with respect to-the carrying means.

10. In an earth movingdevice adapted to be moved across the surface of the ground,

the combination with an earth carrying means having a material receiving edge, of reciprocable hydraulic actuating means, and connecting means including a latch device interposed between the actuating means and the carrier, whereby the position of the material receiving edge thereof'may be varied.

11. In an earth movin device adapted to be moved across the sur ace of the ground, the combination with an earth carrying means having-a material receiving edge,'of reciprocable hydraulic actuating means, and a leverage mechanism interposed between and detachably connectin said hydraulic actuating means and sai carrying means, whereby the position of the material receivingedge thereof may be varied.

12. In an earth moving device adapted to be moved across the surface of the ground,-

the combination with an earth carr g means having a material receiving e ge, of. re-' ciprocable hydraulically operable actuating means, a leverage mechanism interposed between said actuating means and said carrying means, whereby the position of the material receiving edge thereofmay be varied, and

means for adjusting said leverage mechanism to vary the degree of power applied in response to the operation of said hydraulically operable actuating means.

13. In an earth moving device adapted to be moved across the surface of the ground,

the combination with an earth carrying means having a material receiving edge, of a hydraulic actuating mechanism, means for controllmg the operation of said actuating mechanism, and means detachably connect-' with said carr ing means, a hydraulic mechanism for shifting said latching means tovariously position the material receiving edge of the carrying means, and means conveniently positioned with respect to the moving mechanism for controlling the operation of said hydraulic mechanism.

15. In an earth moving device of the class described, the combination with a rotary earth carrying bowl having a material receiving edge and a mechanism for moving said carrying bowl across thesurface of-the ground, of means for coupling the carrying bowl with said moving mechanism, said carrying bowl being pivotally mounted upon said coupling means, the axis of rotation of said bowl extending within the confines thereof, and h draulic actuating means for adjustabl tllting the carrying bowl independently'o the coupling means, whereby the cutting edge of the carrying bowl may be adjustably positioned to compensate for any vertical displacement experienced by the coupling means as it is being drawn across' the, surface of the ground.

16. In an earth moving device of the class described adapted to be drawn across the surface of the ground, an earth carrying means having a material receiving edge, a frame pivotally supporting said earth carrying means, and means for tilting said earth carrying means about its pivotal support including a shiftable member, one extremit thereof adapted to extend over and detachably engage the upper portion of said earth receiving means, and a hydraulic actuator coupled with the opposite extremity of said shiftable member.

17. In an earth moving device of the class described adapted to be drawn across the surface of the ground, a tiltable earth receiving means havin a material receiving edge, a frame for pivotally supporting said earth receiving means, a lug carried on the outer surface of said earth receiving means, a horizontally shiftable member adapted to extend over said earth receiving means and enga e the lug thereon, and a hydraulic actuator or imparting movement to said shiftable member.

18. In an earth moving device of the class described adapted to be drawn across the surface of the ground, a tiltable earth receiving means having a material receiving edge, a frame for pivotally supporting said earth receiving means, a shiftable actuating member adapted to extend over said tiltable earth receiving means, a latch mechanism carried by said shiftable member for engaging the upper portion of said earth receiving means, and a hydraulic actuator for imparting movement to said shiftable member.

19. In an earth moving device of the class described adapted to be drawn across the surface of the ground, a tiltable earth receiving bowl having a material receiving edge and a semi-cylindrical casing section, a frame pivotally supporting said bowl, the pivot being substantially coincident with the axis of said semi-cylindrical casing section, a lug.

carried on the peripheral outer surface of said semi-cylindrical casing sect-ion, a shiftable actuating member adapted to extend over said semi-cylindrical casing section and having means for engaging said lug, and a hydraulic actuator for controlling the movement of said shiftable actuating member.

20. In an earth moving device of the class described adapted to be drawn across the surface of the ground, a tiltable earth receiving bowl having an earth receiving edge and a semi-cylindrical casing section, a frame pivotally supporting said bowl at opposite extremities thereof, a lug mounted on the outer surface of said seml-cylindrical casing section, a substantially horizontally shiftable member adapted to extend over said tiltable bowl, means on said shiftable member for engaging the lug on said bowl, and a hydraulic actuator iston operatively connected with said shiftiible member for imparting rotary movement to said bowl.

21. In an earth moving device of the class described, the combination with a rotary earth carrying means having a material receiving edge, of hydraulically operable means for adjustably controlling the position of said material receiving edge with respect to the surface of the soil, a frame for pivotally supporting said earth carrying means, and mechanical means for urging said hydraulically operable means in a given direction.

22. In an earth moving device of the class described, the combination with a rotary earth carrying means having a material receiving edge, of hydraullcally operable means for controlling the position of said material receiving edge with respect to the surface of the soil, said means including a cylinder, a piston reciprocable therein, and means for operatively engaging the rotary earth carrying bowl, and means for automatically urging said hydraulically operable means in a given direction.

23. In an earth moving device of the class described, a rotary earth carrying means having a material receiving edge adapted to be variously positioned with respect to the surface of the soil, a frame pivotally supporting said rotary earth carrying means, a hydraulic actuator mounted on said frame, said actuator including a cylinder and a piston, and a shiftable member connected with said hydraulic actuator adapted to engage the ro tary earth carrying means to effect rotary movement of said earth carrying means and thereby vary the position of the material receiving edge thereof.

24. In an earth moving device of the class described, a tiltable earth receiving means having a material receiving edge and asubstantially semi-cylindrical casing section, means for pivotally supporting said earth receiving means, a shiftable actuating member adapted to operatively engage said earth receiving means and extending tangentially of the semi-cylindrical section when said section occupies a given position, and a hydraulic actuator coupled with said shiftable actuating member for controlling the movement thereof.

25. In an earth moving device of the class described adapted to be drawn across the surface of the ground, a tiltable earth receiving bowl having a material receiving edge, a stop member associated with the outer portion of the bowl structure, a draft frame having a pivotal connection with said bowl structure, a reciprocable actuating member carried by said draftframe adapted to extend over said bowl and having latch means for positively engaging said. stop member, and power actuated means for selectively moving said reciprocable actuating member in a given direction.

26. In an earth moving device of the class described adapted to be drawn across the surface of the ground, a tiltable earth receiving bowl having a material receiving edge, a stop member associated with the outer portion of the bowl structure, a draft frame having a pivotal connection with said bowl structure, a reciprocable actuating ,member carried by said draft frame adapted to extend over said bowl and having latch means for positively engaging the .opposite sides of said stop member, and

power actuated means for selectively movlid narrates ing said reciprocable actuating member in a given direction.

27. In an earth-moving device adapted to be moved across the surface of the ground, the combination with a rotary earth-carrying bowl having a material receiving edge, power operated means for effecting the rotation of the bowl in a given. direction so as to vary the position of the material receiving edge thereof with respect to the surface of the ground, said power-operated means including ashiftable member adapted to be positively shifted by the bowl as said bowl is rotated in response to a propelling force exerted thereon, and latch mechanism for coupling said power-operated means with said bowl.

28. In an earth-moving device adapted to be moved across the surfaceof the ground, the combination with a rotary earth-carrying bowl having a material receiving edge, and power operated means for effecting the rotation of the bowl in a given directionso as to vary the position of the material receiving edge thereof with respect to the surface of the ground, said power operated means including connections to the bowl for positively rotating the bowl in a predetermined direction, said power operated means and said connections being constructed and arranged to be shifted by the bowl when said bowl rotates in the opposite direction.

29. In an earth moving device of the class described adapted to be drawn across the surface of the ground, a rotary earth carrying bowl having a material receiving edge,

a frame pivotally supporting said earth carrying bowl, actuating means for engaging said bowl to effect the rotation thereof, and a hydraulic mechanism coupled with said actuating means including a cylinder and a piston reciprocable within said cylinder, said piston being shiftable in response to the engagement of the bowl with said actuating means when said bowl is rotated in a given direction.

30. In an earth moving device of the class described adapted to be drawn across the surface of the ground, a rotary earth receiving bowl having amaterial receiving edge,

a draft frame coupled with said bowl, power operated means for rotating said bowl in one direction only including a piston shiftable within a cylinder, and a spring mechanism for shifting said piston in a reverse direction within said cylinder.

In witness whereof, I have hereunto subscribed my name.

RAYMOND L. HARRISON. 

